We have recently found that the visual disorder of adult cats reared in a visually restricted environment is largely reversed following motion detection training. Such recovery after prolonged visual deprivation has not been reported to occur either spontaneously or following other forms of visual training. We now propose to explore the necessary and sufficient training conditions for such recovery and the types of visual disorders which respond to such training. Three groups of visually deprived cats, reared under different conditions, will be studied. The rearing conditions were chosen to produce a severe deficit of visual motion response in one group (8 Hz strobe-reared), of spatial resolution in a second (blur-reared), and of both motion response and spatial vision in the third (dark-reared). determine which aspects of motion detection training are crucial to recovery. The importance of the speed, direction, spatial frequency content and orientation of training stimuli will be assessed. The comparison of three groups of cats will enable us to separate psychophysical effects due to neuronal abnormalities in directional and spatial properties. The training induced visual recovery will be quantified with parallel psychophysical and physiological measures of spatial contrast sensitivity and directional motion sensitivity. The proposed experiments will provide an important information about the reversibility of developmentally induced visual deficits and the type of visual training which maximizes the recovery from these deficits.